Lieutenant Frederic Sartey, a criminal police investigator, is tracking down a female serial killer who operates through dating agencies. In the course of his investigation, he falls in love with one of the suspects, Rachel Baldi.

Suzanne Vogel, the wife of the latest victim, repeatedly identifies Rachel as being her husband’s mirderess. But she fails to convince the two detectives whose minds are stubbornly set on Fabienne, the manageress of the mysterious dating agency.

Will Frederic remain so mesmerised by Rachel as to neglect certain clues, thereby delaying the discovery of the killer, and endangering his own life and his colleagues ?